/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.streaming.util;

import org.apache.flink.streaming.api.watermark.Watermark;

import org.hamcrest.FeatureMatcher;
import org.hamcrest.Matcher;

import static org.hamcrest.CoreMatchers.equalTo;

/**
 * Matchers for {@link org.apache.flink.streaming.api.watermark.Watermark}.
 */
public class WatermarkMatchers {

	/**
	 * Creates a matcher that matches when the examined watermark has the given timestamp.
	 */
	public static Matcher<Watermark> legacyWatermark(long timestamp) {
		return new FeatureMatcher<Watermark, Long>(
				equalTo(timestamp),
				"a watermark with value",
				"value of watermark"
		) {
			@Override
			protected Long featureValueOf(Watermark actual) {
				return actual.getTimestamp();
			}
		};
	}

	private WatermarkMatchers() {
	}
}
